1. Field of the Invention
The present invention relates to a high frequency electronic component incorporating a layered substrate and a plurality of terminals disposed on a bottom surface of the layered substrate.
2. Description of the Related Art
As high frequency electronic components used for circuits processing high frequency signals, those formed through the use of layered substrates have been widely used. A layered substrate incorporates dielectric layers and conductor layers alternately stacked. Inside the layered substrate a circuit processing high frequency signals formed by using part of the conductor layers is formed. Typically, a plurality of terminals are provided at the bottom of a high frequency electronic component formed through the use of a layered substrate. These terminals include: a plurality of functional terminals for inputting and outputting signals relating to functions of the circuit formed inside the layered substrate; and a plurality of ground terminals connected to the ground. The high frequency electronic component is mounted on a mounting board. In this case, the above-mentioned plurality of terminals are bonded to a conductor layer formed on the mounting board through the use of a conductive bonding agent, for example.
As disclosed in Japanese Published Patent Application 2001-285112 and Japanese Published Patent Application 2003-124058, the above-mentioned plurality of terminals are arranged near the periphery of the bottom of the high frequency electronic component in many cases. At the bottom of the high frequency electronic component, a conductor section for grounding is provided in some cases, the conductor section being located in a region surrounded by the above-mentioned plurality of terminals and being connected to the ground. Typically, a conductor layer for grounding that is connected to the ground is provided inside the layered substrate. The ground terminals and the conductor section for grounding are electrically connected to the conductor layer for grounding via through holes provided inside the layered substrate and conductor sections provided on side surfaces of the layered substrate.
Japanese Published Patent Application 2001-244207 discloses a high frequency circuit device comprising: a single circuit board; a plurality of high frequency circuits formed on the circuit board; and ground electrodes provided on the rear surface of the circuit board for the respective high frequency circuits, wherein the ground electrodes for the respective high frequency circuits are isolated from one another with spacing.
As a reduction in size of a high frequency electronic component is promoted, the sizes of terminals are reduced, too. As a result, there arises a problem that the strength of bonding between the high frequency electronic component and a mounting board is decreased. In addition, if the sizes of the terminals are reduced, electrical connection between the ground terminals and the conductor layer for grounding inside the layered substrate is weakened, so that there arise problems such as nonuniformity of electrical potential of conductor portions including the ground terminals and the conductor layer for grounding that should be at the ground potential.